Bu Cheng (布城)

Drawing of a Bu Cheng (highlighted), from 'Ji Xiao Xin Shu (《紀效新書》)'.

Bu Cheng (布城, lit. 'Cloth fortress') was a defensive cloth wall designed by Ming general Qi Ji Guang (戚繼光). It was intended as a substitute of wagon fort in South China, as the muddy terrain of South China made ordinary war wagons unfeasible.

While nothing more than a piece of brick-textured double-layered clothe supported by four wooden poles, Bu Cheng was nevertheless an effective tool, as it could be deployed within minutes at practically everywhere, even right before the enemy's eyes. Bu Cheng did not protect those behind it directly, but concealed their positions and served as an obstacle. It also served as decoy camp when deployed alone.

To prevent enemy troops from simply tearing the cloth down, Bu Cheng was always deployed together with cheval de frise and caltrop. It could also be reinforced with cotton blanket to defend against arquebus rounds. A combination of blanket-reinforced Bu Cheng, chevaux de frise and caltrops could quickly turn a vulnerable position into a well-defended field fortification.